HD4400 chip suddenly doesnt support UHD resolution on external device anymore

[EKhan]

Hello,

I have a Lenovo T440 laptop with an Intel HD4400 chip. The laptop has a mini display-port connection which I used to attach an UHD TV via HDMI (DP to HDMI converter cable). It worked very well and the laptop was able to play UHD material with MPC-HC and madVR. I was fiddling around with the settings to get better results (switching to intel quicksync instead of DXVA2 etc.)

At some point the video driver crashed and I decided to reboot the machine. After the reboot was done, the UHD television resolution switched to 1080p and windows/intel control panel claim that this is the maximum supported resolution. Obviously this isn't correct as I have just used its UHD resolution.

I dont know what to do to fix this...

It is not the TV, because I am still using it in UHD mode with my desktop computer.

It is not the HDMI cable, because it works fine between my desktop and the TV.

It is not the miniDP to HDMI converter or the miniDP port, because when I reboot my device to Debian/Linux I can still use the UHD resolution.

I can only think of the intel driver or windows, which are somehow loading the wrong settings for the device.

I've removed the intel driver via DDU already and reinstalled the newest version, no dice.

[EstebanA_C_Intel]

Hello, owah:

Have you tested with the default drivers from Windows?

You could also test your system with the drivers provided by your OEM.

https://downloadcenter.intel.com/product/81497/Intel-HD-Graphics-4400-for-4th-Generation-Intel-Core-Processors Drivers & Software from Intel®

I look forward to your outcome with this.

Regards,

Esteban C

[EKhan]

Hey!

the default windows drivers don't recognize the external display at all. And yes I have tried the OEM driver, same problem.

I forgot to mention that the OS is Windows 10. Also there is a chance that we might never find out how this bug came to exist because out of frustration I have used the built in reset function of Windows 10 to reset my whole system. Even after I did this, the display still claimed to be 1080p.

I have then completely formatted my device and lo and behold now I can use the UHD screen again.

Because the Windows reset didn't fix the problem either I assume it has to do something with a faulty registry key, because that's how the issue persisted even when removing drivers/resetting the system.

[EstebanA_C_Intel]

Hello, owah:

I am glad to hear that you were able to get the desired resolution from your system.

Yes, it could have been a registry key issue.

If you require any further information or support, feel free to contact the Intel® Communities again.

Regards,

Esteban C

[EKhan]

Hello,

I have the same problem again, out of nowhere my Laptop thinks that my UHD television has a max. resolution of 1920x1080. As soon as I reboot to (Arch) Linux, I can select 3840x2160.

[EstebanA_C_Intel]

I am sorry to hear that owah; Have you tested the latest drivers for Windows 10*?

They were recently released: https://downloadcenter.intel.com/download/25951/Intel-Graphics-Driver-for-Windows-10-15-40-4th-Gen-?product=81497 Download Intel® Graphics Driver for Windows® 10 [15.40][4th Gen]

I look forward to hearing from you.

Regards,

Esteban C

[EKhan]

Hey,

I have tried installing the driver via the .exe. The installer aborts and claims that this driver isnt compatible with my system. So I have downloaded the packed .zip and extracted the driver to manually install it. This didn't work either because my system claimed that the installed driver is already new enough.

So what i have done is remove the current driver and then installed your supplied driver from scratch. My system now accepted the driver but the TV still only outputs 1080p. Something else I have noticed is: I am not able to play audio through HDMI anymore, this must be related to the laptop recognizing the TV only as a 1080p screen without speakers.

I'd like to mention again, that just 40 minutes ago I have used my Arch-Linux install to play UHD content. So it can't be the cable/TV/intel HD card.

But the problem should rather be located within either the OS or the intel windows driver.

[EstebanA_C_Intel]

owah:

Thank you for you answer on this.

Please make sure you have all window updates installed in your system, you can also use the system file checker from windows to troubleshoot this, link added below:

http://windows.microsoft.com/en-us/windows-10/using-system-file-checker-in-windows-10 Using System File Checker in Windows 10 - Windows Help -

Due to the fact you are using the generic drivers from Intel on an OEM system we cannot make sure they are going to work properly, for that reason, I would like to recommend you to contact the manufacturer of your device to find any additional drivers to be used or remaining troubleshooting to be performed.

As you said the cables and hardware are working fine with the tests performed on the other OS so the remaining options as the failure will be OS or drivers.

Any further feedback on this after getting in touch with the OEM would be great to have for future references.

If any additional questions or inquiries are present, feel free to contact us back.

Regards,

Esteban C